I think the Stihl (not sure who makes it) might be the better of the three but the X25 ain't no slouch , the GB is the nicest for feel but the other two will make easier work of the tougher wood .
This Ochsenkopf , about the same length as the other three seams to be the best of the bunch but it might be a little heavier , I'll have to dig them all out some day and weigh them .
The GB has a built in tin protector , it works beautifully so I made one for the Ox , I formed a heavy gauge piece of sheet metal around it the welded and pinned it , works like it should .
I'm 5'8" , I prefer to split on the ground in a tire or a piece of 2x12 , I prefer the shorties for aim and speed but I also like my Isocore lol